1. Field of the Invention
This invention relates to a clutch apparatus provided with a diaphragm spring for use in an automotive vehicle.
2. Description of the Related Art
A prior clutch apparatus is known from Japanese Laid-Open Publication No. 58-17227. As shown in FIG. 9, a plurality of equally pitched tabs 2 are provided on an internal circumference 1a of a clutch cover 1. A plurality of pivot rings 4, each of which acts as a fulcrum point for a diaphragm spring 3 are supported on the clutch cover 1 by bending a top end portion 2a of each tab 2 toward a pressure plate 5 which is arranged in the clutch cover 1. Each tab 2 is, as shown in FIG. 10, snugly fitted in an opening portion 3b formed at an outer end of a slit 3a of the diaphragm spring 3. As shown in FIG. 11, each tab 2 has a width which is only slightly shorter than the width of the opening portion 3b so as to provide the snug fit and prevent the clutch cover 1 and the diaphragm spring 3 from rattling therebetween.
However, the foregoing clutch apparatus, is not easy to assemble due to a requirement for a strong plural pivot rings 4 and the diaphragm spring 3 into the plural tabs 2, and there is a fear that the diaphragm spring 3 will not work smoothly because of the need for the strong connection force between the tabs, rings and spring.
In light of the above-mentioned drawbacks, recently, a clutch apparatus has been proposed which is equipped with a tab 2', 2" as shown in FIG. 12 or FIG. 13. The tab 2' (shown in FIG. 12) is provided with a central slit 6 at a top end portion 2a' thereof as well as the tab 2" (shown in FIG. 13) is provided with cutout portions 7 at both sides of a top end portion 2a" thereof.
However, the clutch apparatus provided with either of the tabs 2', 2" has the same problem as the clutch apparatus of FIGS. 9-12.